ConDB Web Access Python API

This document describes the Python API for remote access to the ConDB web server.

class condb.ConDBClient(url, username=None, password=None)
__init__(url, username=None, password=None)

Initializes the ConDB client

Parameters:

  • url (str) – Server URL prefix

  • username (str) – Optional username

  • password (str) – Optional password

get_data(folder, t0, t1=None, tag=None, tr=None, data_type=None, channels=None, as_named_tuples=False)

Get data from folder

Parameters:

  • folder (str) – Folder name

  • t0 (int or float) – Tv to get data for

  • t1 (int or float) – Optional, if specified, the data will be returned for the t0…t1 time interval

  • tag (str) – Optional, return data from the tagged database state

  • tr (datetime or int or float) – Optional, return data for previous state of the database identified with tr

  • data_type (str) – Optional, return sata for the given data source. Default: “”

  • channels (list or tuple or int) – If int, return data for single channel If tuple, return data for a range of channels, e.g.: (100, 151) If list, return data for list of channels or channel ranges, e.g.: [10, 15, (23, 27)]

  • as_named_tuples (bool) – If true, return the data as collections.namedtuple’s. Otherwise, native Python tuples

Returns:

columns - list of column names generator - producing tuples or collections.namedtuple’s, one per data row

Return type:

tuple (columns, generator)

put_data(folder, data, columns, tr=None, data_type=None)

Add data to folder. Requires the username and password.

Parameters:

  • folder (str) – Folder name

  • data (list) – List of tuples: [channel, tv, …]. Order of columns after tv is the same as in columns

  • columns (list) – Must begin with [“channel”, “tv”]

  • data_type (str) – Optional data source, default = “”

  • tr (datetime or int or float) – Optional Tr to associate the data with. Default = current time

search_data(folder, tag=None, tr=None, data_type=None, channels=None, conditions=[], as_named_tuples=False)
Search the timeline determined by (tag, tr, data_type) for data rows

matching the conditions expressed in terms of the data column values

Parameters:

  • folder (str) – Folder name

  • tag (str) – Optional, return data from the tagged database state

  • tr (datetime or int or float) – Optional, return data for previous state of the database identified with tr

  • data_type (str) – Optional, return sata for the given data source. Default: “”

  • channels (list or tuple or int) – If int, return data for single channel If tuple, return data for a range of channels, e.g.: (100, 151) If list, return data for list of channels or channel ranges, e.g.: [10, 15, (23, 27)]

  • conditions (list of tuples) – Conditions cpecified as tuples: (“column_name”, op, value) column_name is a name of a data column op is a string “<”, “<=”, “=”, “!=”, “>=”, “>” value is a string, boolean, numeric or None

  • as_named_tuples (bool) – If true, return the data as collections.namedtuple’s. Otherwise, native Python tuples

Returns:

columns - list of column names generator - producing tuples or collections.namedtuple’s, one per data row

Return type:

tuple (columns, generator)

tag_state(folder, tag, tr=None, copy_from=None, override=False)

Add tag to a database state. Requires the username and password.

Parameters:

  • folder (str) – Folder name

  • tag (str) – Tag to add

  • tr (datetime or int or float) – Tr, optional. Identifies the database state to tag. Default: current state

  • copy_from (str) – Tag the same state as an existing tag

  • override (boolean) – If the tag already exists, move the tag to the new Tr